Fluid heater



' Dec. 20, 1938. R. A. FoREsMAN I FLUID HEATER Filed Oct. 23, 1935 4 Sheets-Sheet l INVENTOR R BE T H. FbREsMnN To g.

R. A. FQRESMAN FLUID HEATER Fil ed Oct 23, 1955 4 Sheets-Sheet 2 INVENTOR 'r H-FBREs mm.

ROGER DecfZO. R v.

FLUID HEATER Filed Oct. 23, 1955 4 SheetsSheet 5 INVENTOR' I ROBERT H. FbREs MHN WITNE ES:

ATTORDZL/ R'." A. FORESMAN FLUID HEATER 1 Filed Oct. 25,. 1935 4 Sheets-Sheet 4 v INVENTOR RoBERT/Z FEREs MAN.

I ATTO EY WITN sEs;' 5Q

. Patented Dec. 20, 1938 FLUID, HEATER Robert A. Foresman, Prospect Park, Pa., assignor to Westinghouse Electric & Manuf acturing Company, 'EastPittsburgh, 2a., a corporation of Pennsylvania Application October 23', 1935, Serial No. 46,241 21 Claims. (01. 122-40) i Myinvention relatesto fluid heaters of the type disclosed in my vcopending application, Serial No.

I 658,334,'filed February 2 4, 1933, and it has for an -object to provide improved apparatus of this akin'd; 1 V A further object of my invention is to provide i V an improved heater for use witha fuel burning structure of the rotatable annular grate type, and having a magazine disposedtherein. for the 10 gravitational feed of fuel tothe grate.

I Itis'a'further objectof my invention to pro- I vide animproved heater of this type wherein a substantial 'portion' of theweight of the fuel in the'hopper is, removed. from the grate;

15 neon further object-of myinvention isto arrange; aheater of this type, theiaccessopeningsfor the'admission of fuel andfor the removal; of refuseonone side of the heater.

, Still further objects of my invention are to prozou videian improved heating structure which may fb'e manufactured in standardized sections'rfor obtaining'various sizes, and ratings and which may 1 be. operated with a minimum of attention over longjperiods;

7 These and other objects are. effected by my 7 invention aswill be apparent from thefollowing description and claims taken in connection with I the accompanying drawings, forming a, part of this applicatiomin which:

" ;Fig.- 1 is a front view or my improvediheater, portions of which are shown in cross section,

the intermediate portion of the heater and the grate supporting base thereof being shown in section and taken along the line II of Fig. 2 and 35 the lower heater portion being infcr'oss section and taken along the line -A-A'of Fig. 2;

, 'FigQZis a plan view of the apparatus shown in Fig. 1; Fig. 3 is a sectional viewtaken'along the line I r fiilof Fig.1 and Fig.

I Fig. 4 isv a sectional View taken along the line.

flIV -IV of Fig l with portions broken away-for the, sake of clearness, which portions are indicated by the offset line'IVIV of Fig. 5;.

45 Fig- 5 is a'developed view of the apparatus shownin the preceding views;

V fFigqG is a developed view of a modified detail of'Fig.';5;fand, I i A liigr 1.7 is a sectional view ofa modified detail 50 ofthe apparatus shown in Figs. 1 to 5, inclusive. Reference will now be had to the'drawing's in which my'im proved fluid heater is generally'indicated by thereference' numeral l and which is supporte d on a base member Thelatter in:

' 5 cludesinner andouteriwalls I 2 and I3 upon which includes awater-space 23. Thewalls l9 and 22 an annular grate structure I4 is rotatably carried. The grate may be rotated in any suitable manner such as, for example, by a reciprocated pawl and ratchet mechanism IS, the driving means therefor being omitted as itforms no part 5 of the present invention.

The heater structure l0 preferably includes an upper and lower section l6 and I! and an intermediate'section l8 arranged in superimposed relation. I have disclosed but one intermediate 10 section 8 but it will be understood that'a plurality .of sections may be employed, the number of which is determined by the rating of the boiler or the amount of heat transfer surface necessary.

Theheater l0 includes an outer wall I9 having a space 2| formed therein for the medium to be heated, such'as, for example, water. An inner concentric relation wth the outer wall l9 and are respectively carried by the walls l3 and I2 of the base II and are alined, substantially, with the outer and inner circumferences of the annular grate l4.

Communication between the water spaces 2| of the various sections Hi to l8, inclusive, is provided by conduits 24, as the terminal portions oif-the wall |9 of each section is closed, as best shown in Fig. 1. This construction eliminates the necessity of largefgaskets between the wall |9 of each section. The inner wall or'column' 22 of each section is open where it connects with the wall of an adjacent section, the open ends being provided with internal flanges secured together by bolts 26. A gasket 21 may be employed for obtaining a fluid-tight connection between the flanges 25.

The heater I0 includes a plurality of circumferentially'spaced wall members 28, 29, 3|, and 32 which connect the inner and outer walls 22 and I9 and which are. preferably provided with respective water spaces 33 to 36, inclusive. The water'spaces 33 to 36 communicate with the spaces 2| and 23 as best shown in Figs. 3 and 4.

The complementary portions of the walls 28, 29, 3|, and 32 which are included in the various sections l6, I1, and I8 are clearly shown in the developed view (Fig. 5).

The circumferentially spaced walls 28 and 29 divide the annulus between the outer and inner Walls I9 and 22 into a pair of arcuate chambers 31 and 38, the first of which is a fuel receiving grate M for defining a fuel discharge orifice 39, through which fuel is carried into the combustion chamber 38 when the grate is rotated in a clockwise direction as viewed in Fig. 3, or in the direction indicated by the dot and dash arrow of the developed view, Fig. 5. The depth of the fuel bed may be varied by an adjustable plate 4 l movable in avertical direction by adjusting nuts 42 and rod 43.

The upper or fuel supporting surface of the grate l4 may be inclined downwardly toward the outer periphery of the grate and the lower edge of the plate 4| disposedhorizontally for pro viding a thicker bed of fuel adjacent the outer periphery of the grate. The inclined grate, furthermore, facilitates the removal of rash therefrom and further reference to the removal of ash will be made hereinafter. I have found that, as the grate is rotated, the fuel tends to move inwardlypf the grate, dueto the friction between the fuel and the outer wall 19 of the combustion chamber. Therefore, with a fuel bed of initial constant depth, the bed becomes progressively thinner at theouter periphery as the grate rotates and combustion becomes uneven, complete combustionof the fuel at the outer periphery of the grate being prior to the complete combustion ofthe fuel adjacent inner portionsof the grate I obviate this undesirable operat on by inclining the grate so-that a fuel bed,-which in-' creases indepth from the inner to the outer .por-

tionsof the grate, is admitted to the combustion chamber. and, therefore, compensate for the movement of .fuel inwardly .of' the grate.

Both walls 28 and 29 preferably connect with. atop wall or drum M, the water spaces 33 and 34 communicating with the interior of the drum 44. The wall 29 includes anoifset portion 45 which is spaced above the grate and which extends toward the wall 2B,'w hereby afloor is. defined for a portionof the magazine 31.. The offset portion 45 terminates-in spaced relation with the wall 28 to define a passage 46 through which fuel passes to the grate. A wall portion 41 extends downwardly from the end of the offset portion and terminates adjacent the grate I4. The wall portions 45and M are preferably provided with water spaces 48 and 4 9 which communicate with the space 34 of wall 29. A false bottom 5| may be provided for the magazine 31, which bottom may be inclined toward the passage 45 at an angle equivalent to the angle of repose of the fuel.

, It will be apparent from the foregoing description that a substantial portion of' the Weight of area of the grate is increased in an amount equivalent to the grate area lying beneath the bottom wall 45-and, asthis wallisprovided with spaces for water to be heated, the heat transfer surface of the heater is increased.

Fuel is admitted to the space 3'! through an opening 52, preferably in the front of the heater, and closed by a door 53. For the'convenience of the attendant, I locate the ash removal opening on the same side of the heater as the fuel opening .52 which openings are alined substantially in a vertical plane. The ash removal opening is best, shown at 54 inFig. 4 and is formed in the, outer wall I 9 and beneath the bottom wall 45 of the magazine. .Refuse -.of combustion may be deflected outwardly of the grate toward the opening 54 by one or more plates 55 secured to the heater structure in any suitable manner.

When a plurality of plates 55 is employed, they are spaced radially of the grate and are disposed at a tangent thereto as best shown in Fig. 4. As the grate M is rotated, the ash carried thereby engages the plates 55 and is moved radially of the grate. and passedthrough the opening 54 to an ash pit 55, from which the refuse may be removed through an access opening 51. As statedheretofore, the fuel supporting surface of the grate M is inclined downwardly toward the outer periphery of the grate, which inclination facilitates the movement of ash radially of the grate. Y

It may be desirable in somecases to provide adjustments for the deflecting plates 55, so that the angle at which the plate rests with respect to the moving body of ash may be varied. Ac-

cordingly, I have shown the inner plate 55 provided with an adjusting screw 5i, which may be rotated to swing the plate in a horizontal plane. The solid and the dot and dash lines in Fig. 5 show the inner plate 55 adjusted to different positions, The inner end of the adjustable plate 55 is supported in any convenient manner to permit movement of the plate. disclosed, the plate 55 merely rests against the inner wall 22. The plate 55 may befirmly held in its adjusted position by a bolt 62.

A'dust tight housing 58 is provided for the pit 55 in which the accessopening 51 is formed. Preferably, containers 59, indicated by dot and dashlines in Fig. 4, are employed for collecting the ash as it passes throughthe opening 54, which containers are removable from the housing 58 through the door 51. The ash pit 56 extends into thebase H and is defined therein by radial walls 53 which divide the base ll into arcuate chambers. One of these chambers is the pit 56 and the other chamber, indicated at 64, is a wind box disposed beneath the portion of the fuel'bed within the combustion chamber 38. The walls 53 are aligned substantially with the magazine walls 28 and 29. (See Fig. 5.) As disclosed in my copending application Serial Number 658,334, referred to heretofore, the wind box 54 may be divided into a pluralityof chambers with respective dampers for regulating the flow of air to the chambers.

The upper portion of the ash pit 56 is covered,

by a horizontal plate 65 upon which a thin layer of ash may collect and which cooperates with the grate structure to provide a seal for confining the passage of air from the wind box 64 to the portion of thegrate where combustion is effected. The grate structure l4 includes a plurality of radially-extending arms 55 which engage said layer of ash, as shown in Fig. 5, and preventpassage of air to the grate portions be- In the embodiment I neath the magazine 31 or the portion of the grate wher the combustible is burned out.

The active portion of the grate which supports burning fuel lies substantially between the walls 28 and 29 within the arcuate combustion chamber 38. An arch 6?, preferably provided with a water space 58, is disposed above-the grate l4 and extends from the wall or bafile 32 to the magazine wall 29, the space 68 of the arch communicating with the water spaces 35 and 3 5. The oiftake for gases is indicated at 69 adjacent the top of the combustion chamber and a tortuous path for the flow of the gases above the arch 51 is provided by the walls or bafiles 32 and 3!. The

; relation with thearch and is connected "at its upper end .to the drum or-wall '44, thewater space-35 being, 'preferably,*incommunication withthe space within the drum. The path of --the"-fio w 'of gases through the combustion chamberis'shown by arrows inFig. 5,

.ly,;in 'the outer and top walls l9 and 44, and are provided with suitable closures.

The openings TI and l2'are preferably formed, respectively,

" spaces and which are secured tothe outer and bytubes 1m and 12a which traverse the water innermembersof the walls whereby further reenforcing of the walls is obtained and additional heat, transfer surfaceprovided. w

]Water to be heated, or vaporizedlis admitted to the outer wall I 9 of the lower section, as shown at :13. 'A portion of the entering water may be' admitted to the intermediate section as shown at 14."- Heated'water or-steam'iS removedfrom the upperwall or drum 44through one or more connections 15. A gauge glass 16 is providedfor 'thehe'ater when operating to produce steamyfor 1 viewing the water line which is 30 a a ft'atedbythe operating mechanism 15, and coal maintained 'within the drum 44; 'Whe n in operation, the grate 14 is slowly ro- .;1fro'm the magazine I3 is advanced thereon into ithecornbustion space 38, the depth of thefuel bed "being determined by theelevation of the fuel lev- {eling device 4| Air forcombustion is delivered many-suitable. manner to the wind box 64 and 'passes'through the grate l4 tothe fuel for promoting ccmbustion;thereof.- The fuel is progressively burned as it'advances through the combustcreasmg and that of the ash increasing. The

tifonfchamber 38, the thickness of the fuel decombustible is practically all burnt out of the coal j by the time it passes beneath the wall member 29 so that only refuse remains. The latter is des Excess air delivered to the combustion chamber fiected from the grate I4 as heretofore/described T 38} maybe bled off, preferably to the stack, by nieans of a pipe 18 controlled by a damper 19.

- "The tion chamber 38 through the ash discharge open- [ing 54 asshown; f The amount of excess air deliveredtothe combustion chamber may, thereforefbecontrolled by'regulating" the by-pas's dampers lfi sothat the'furnace is operated at highefficiencyf This means for regulating the amount of excess air delivered to the combustion chamber. is disclosed and claimed inmy copendin'g application, Serial No.26,600, filed June 24,: I, 193 5," and assigned to the Westinghouse Electric 8: '60 a =wa er to be heated enters the outer wall- H! of Manufacturing Company. I

the section ll and is heated orvaporized" as it rises-to the upper drum44 through the inner chamber 23 and through-theconnecting conduits .Th 'evarious walls and bafiles and the arch be- ;ing' provided with water heatingspaces present a large amount of heat'transfe'r' surface to the fire. It'will' be apparent that these surfaces, being for the most part vertical will 70" a QInFig. '7, I have shown a transverse section of not collect soot or dust tc'any'material degree.

almodificationo'f my improved heater having a v plurality of spaced arcuate wall members 8| arranged withinthe combustion chamber 38 for 013-; taining additional heattransfer' surface. The

pipe 78 may communicate with the combuswalls 8| are disposed substantially in concentric relation with the outer wall I9 and extend vertically within the combustion chamber38. The

walls 8| may intersect one or more of the circumferentially spaced walls or baffles 32 and 34 and are providedwith spaces 82 for fluid to be heated, which spaces 82 are in communication with the spaces 35 and 36. The arcuate walls 8| are spaced from the outer and inner walls [9 and Hand from each other to provide passages for the gases of 1 combustionJAs the walls 8| are vertically dis- The refractories 83 may be disposed on angle members 184 secured to the inner and outer walls 19 and 22.

From the foregoing, it will be apparent that I have provided an improved fluid heater or boiler for a rotatable annular grate and having a fuel magazine arranged therein for the gravitational feed of fuel to the grate, which magazine is so arrangedthat a substantial portion of the weight of the fuel-isremoved from the grate. Furthermore, the arrangement of the magazine within the heater is such that the removal of refuse from the grate may be effected beneath the magazine, whereby the fuel admission opening to the magazine and the ash removal opening may be disposed on the same side of the heater structure.

By dividing the heater into sections which are superimposed, I am enabled tobuild relatively large boilers for steam heating service, which may be admitted through existing door openings of the premises where the heater is to be installed. Various sizes and ratings may be obtained from a few standardized sections, as additional intermediate sections l8 may be employed where additional heat transfer surface is required. The speed of'the' grate may be varied for different boiler ratings so that, with a few sizes of standardized sections, a relatively large number of heaters of various sizes and ratings may be economically produced.

While I have shown my invention in several forms, it willbeobvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from thespirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

. What I claim is:

1. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the. perimeter of the grate, first and second circumferentially spaced walls eX- tending inwardly from the outer Wall and joined of, whereby, the horizontal area of the magazine adjacent the grate is less than the horizontal area of the magazine remote from the grate; means for admitting fuel to the magazine and means for rotating the grate. b

2. The combination as claimed in claim 1 in which the fluid heater is formed of a plurality of complementary sections having means providing for the flow of fluid therebetween.

3. The combination as claimed in claim ll having means for varying the depth of'fuel delivered to the grate through said fuel discharge orifice.

4. The combination as claimed in claim I having means spaced from said first circumferene tially spaced wall for deflecting refuse of combustion from the grate.

5. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the perimeter of the grate, first and second circumferentially spaced walls extending inwardly from the outer wall and joined at their inner ends for defining a fuel magazine and a combustion chamber above arcuate portions of the grate; said first circumferentially spaced wall having a portion thereof spaced above the grate for defining, therewith, a fuel discharge orifice, said second circumferentially spaced wall terminating adjacent the grate, one of said circumferentially spaced walls having an offset portion extending toward the other circumferentially spaced walls so that the portion of the fuel magazine adjacent the grate is of smaller horizontal area than the portion thereof remote from the grate, means for admitting fuel to the magazine, and means for rotating the grate.

6. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the perimeter of the grate, first and second circumferentially spaced walls extending inwardly from the outer wall and joined at their inner ends for defining a fuel magazine and a combustion chamber above arcu-' discharge orifice, one of said circumferentiallythe grate is of smaller horizontal area than the portion thereof remote from the grate, means spaced circumferentially from the fuel discharge orifice for removing refuse from the grate, means for admitting fuel to the magazine, and means for rotating the grate.

7. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the perimeter of the grate, a magazine arranged for the gravitational feed of fuel to the grate and including a first wall extending inwardly from the outer wall and having its bottom portion spaced above the: grate for defining a fuel discharge orifice and a second wall extending inwardly from the outer wall and circumferentially spaced from the first wall, said first and second walls being connected at their inner ends, said second wall having a portion thereof extending substantially in a horizontal plane and forming a bottom for a portion of the magazine; means associated with the second wall for deflecting refuse from the grate, means for admitting fuel to the magazine and means for rotating the grate.

8. The combination as claimed in claim 7 having a false bottom memberarranged within the magazine above said. horizontally extending portion of the second wall and at an angle thereto.

9. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the perimeter of the grate, a magazine arranged for the gravitational feed of fuel to the grate and including first and second circumferentially spaced walls extending inwardly from the outer wall and joined adjacent the central portion of the grate, said first circumferentially spaced wall having a portion thereof spaced above the grate for defining a fuel discharge orifice, said second circumferentially spaced wall including upper and lower portions extending substantially in a vertical plane but circumferentially displaced with respect to each other and including a portion connecting the upper and lower portions for defining a bottom for a portion of the magazine, means for deflecting refuse from the grate beneath the horizontal portion of the wall; means'for admitting fuel to the magazine, and means for rotating the grate. 10. In fluid heating apparatus, the combination of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above they perimeter of the grate, a magazine arranged for the gravitational feed of fuel to the grate and including a first wall extending inwardly from the outer wall and having its bottom portion spaced above the grate for defining a fuel discharge orifice and a second wall extending inwardly from the outer wall and circumfeerntially spaced from thefirst wall, said first and second walls being connected at their inner ends, said second wall having a lower portion thereof extending toward said first wall for supporting a portion of the fuel in the magazine, means disposed beneath said portion of the second wall for deflecting refuse of combustion from the grate, means for admitting fuel to the magazine and means for rotating the grate.

11. The combination, as claimed in claim 10 having means for adjusting the refuse deflecting means with respect to the grate.

"12. The'combination as claimed in claim 10 wherein the refuse deflecting means includes a plurality of deflecting plates having their lower edges disposed adjacent the upper surface of the grate and radially spaced from each other, said plates being tangentially disposed with respect to the grate.

13. In fluid heating apparatus, the combination of a rotatable annular grate, inner and outer walls arranged above inner and outer portions of the grate and enclosing respective spaces for fluid'to be heated, a fuel magazine arranged above an arcuate portion of the grate and including first and second walls connecting theinner and- 1 of the second magazine wall for moving refuse of combustion from the grate, means associated with at least one of said devices for adjusting the angularity'thereof with respect to the grate, I means for admitting fuel to the magazine, and

means for rotating the grate.

14. In fluidheating apparatus, the combination of a rotatable annular grate, a wall member eter of the grate, a fuel magazine disposed above forming a portion of the heat transfer surface of the fluid heater and arranged above the'periman arcuate portion of the grate for the gravita- "tional feed of fuel thereto and including first andsecond walls circumferentially spaced from each other and extending ,inwardly'fromsaid wall member, said first magazine wall terminat- I ing in spaced relation above the grate for defining afuel discharge orifice, said second magazine wall having a portion thereof. extending toward the first magazine wall for supporting a por-v tion of the fuel in the magazine, means arranged below said portion of the second magazine wall for removing refuse of combustion from the grate, said last-mentioned means including a passage through which refuse is discharged and adeflecting device extending across the grate for moving refuse toward said passage as the grate ,1 isrotated, means for admitting fuel to the mag- ,azine, and means forrotating the grate.

I 15. The combination as claimed in claim 14' in which said fuel admission means includes an opening through which fuel is deposited in the Q magazine and which is alined, substantially, in

sage.

a'vertical plane above said refuse discharge pas- 16. In, fluid heating apparatus, the combina- I tion of a rotatable annular grate, an outer wall having spaces therein for medium to be heated and arranged above the perimeter of the grate, a magazine arranged for the gravitational feed of fuel to the grate and including first and sec- "nd circumferentially spaced walls, extending inwardly from said outer wall and joined at their inner ends and including a bottom wall Ispaced above the grate and connected to one of said circumferentially spaced walls, said bottom wall extending across a portion ofv the magazine toward the other of said circumferentially spaced walls, wherebya support for a portion of the fuel in said magazineis defined, one of said magazine walls terminating above the grate in spaced relation for defining an orifice through which fuel is passed as the grate is rotated, means spaced from said orifice for deflecting refuse from the "grate, means for admitting fuel to the magazine,

and means for rotating the-grate.

17. In fluid heating apparatus, the combination of a rotatable annular grate, inner and outer walls'jarranged above the inner and outer peripheries ofthe grate for defining a combustion chamber above the grate; said inner and outer walls enclosing respective'spaces for fluid to be heated, a radially extending wall connecting the *inner'and outer walls and having a space therein communicating with the spaces enclosed by the inner and outer walls, and'anarcuate wall disfposed'within the combustionchamber intermej diate' of the inner and outer walls and having ya spaceformed therein for fluid to be heated,

said arcuate wall intersecting the radially extending wall and having its fluid space communicating with the space of the radially extending wall.

18. In fluid heating apparatus, the combination of a rotatable annular grate, inner and outer Walls arranged above the inner and outer peripheries of the grate for defining a combustion chamber above the grate, said inner and outer walls enclosing spaces for fluid to be heated, a radially-extending wall connecting the inner and outer walls and having a space therein communicating with the spaces enclosed by the inner and outer Walls, and an arcuate Wall disposed within the combustion chamber intermediate of the inner and outer Walls and having a space formed therein for fluid to be heated, said fluid space of the arcuate wall being in communication with the fluid spaces of said inner and outer walls and of said radially-extending wall.

19. In fiuid heating apparatus, the combinationof a rotatable annular grate, a boiler structure disposed above the grate and including inner chamber to the combustion chamber, and means including one of said radially extending Walls for levelling the fuel carried into the combustion chamber by the grate, said grate having its fuel supporting surface sloped downwardly from the inner to the outer periphery thereof, whereby the thickness of the bed of fuel carried by the grate into the combustion chamber increases progressively from the inner to the outer peripheries of the grate.

20. In fluid-heating apparatus, the combination of a rotatable circular grate, a structure having spaces therein for fluid to be heated and defining a combustion chamber above a segment of the grate, and a magazine for fuel disposed above a second segment of the grate and beside a portion of the combustion chamber, said structure including a substantially horizontal wall member disposed below the magazine and having a space therein for fluid to be heated and an opening for the passage of fuel from the magazine to said second segment of the grate.

21. In a fluid heating apparatus, the combination of a rotatable circular grate, a fluid heating structure associated with the grate and having eluding an opening for the passage of fuel from the magazine to the grate, and fluid cooled means extending transversely of the grate for defining said first and second segments of the grate.

- ROBERT A. FORESMAN. 

